"which of these books is yours, Kate” asked the old man.
`->`The old man asked Kate which of those books was hers.
`=>` Cấu trúc câu tường thuật :
What/When/… + S1 + asked + S2 +Verb(chia thì quá khứ đơn)
`<=>` S1 + asked + S2 + V(chia thì quá khứ đơn)